摘要 |
<p>The invention provides a valve timing changing device, by which a vane rotor is kept at a central position when the engine is started to prevent sloshing, knocking noise and wearing. The device includes a housing rotor (30), a vane rotor (2), an advance angle passageway (13) communicated with an advance angle chamber for operating oil to pass through, a lag angle passageway (14) communicated with a lag angle chamber for the operating oil to pass through, and a lock mechanism (40) which locks the vane rotor at a center position relative to the housing rotor and unlocks the lock by means of the hydraulic pressure of the operating oil. The lock mechanism includes an advance angle lock bar (42) and a lag angle lock bar (44). The advance angle passageway (13) guides the hydraulic pressure to unlock the lock of the advance angle lock bar and the lag angle lock bar, and the lag angle passageway (14) guides the hydraulic pressure to maintain the unlocking of the lock of the lag angle lock bar. The vane rotor is kept at the central position when the engine is started so as to ensure the stable starting performance of the engine.</p> |